President Obama is taking executive action to protect millions of undocumented immigrants from deportation.

His plan has been a tough sell to the American people, especially with the new Republican-controlled Congress. But many experts agree that some of the arguments against immigration are based on misguided information.

Here are 5 myths about undocumented immigrants, and why they're wrong.

Myth # 1: They don't pay taxes

Undocumented immigrants are already U.S. taxpayers.

Collectively, they paid an estimated $10.6 billion to state and local taxes in 2010, according to the Institute on Taxation and Economic Policy (ITEP), a research organization that works on tax policy issues. Contributions varied by state. In Montana they contributed $2 million. In California, more than $2.2 billion. On average they pay about 6.4% of their income in state and local taxes, ITEP said.

A 2007 Congressional Budget Office (CBO) report on the impact of undocumented immigrants on the budgets of local and state governments cited IRS figures showing that 50% to 75% of the about 11 million unauthorized U.S. immigrants file and pay income taxes each year.

A 2013 CBO analysis of the failed bipartisan bill introduced by the so-called "gang of 8" that would have created a path to legal status for many undocumented immigrants found that increasing legal immigration would increase government spending on refundable tax credits, Medicaid and health insurance subsidies, among other federal benefits. But it would also create even more tax revenue by way of income and payroll taxes. That could reduce deficits by $175 billion over the first 10 years and by at least $700 billion in the second decade.

ITEP estimates that allowing certain immigrants to stay in the country and work legally would boost state and local tax contributions by $2 billion a year.

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Myth # 2: They don't pay into Social Security

The truth is that undocumented immigrants contribute more in payroll taxes than they will ever consume in public benefits.

Take Social Security. According to the Social Security Administration (SSA), unauthorized immigrants -- who are not eligible to receive Social Security benefits -- have paid an eye-popping $100 billion into the fund over the past decade.

"They are paying an estimated $15 billion a year into Social Security with no intention of ever collecting benefits," Stephen Goss, chief actuary of the SSA told CNNMoney. "Without the estimated 3.1 million undocumented immigrants paying into the system, Social Security would have entered persistent shortfall of tax revenue to cover payouts starting in 2009," he said.

As the baby boom generation ages and retires, immigrant workers are key to shoring up Social Security and counteracting the effects of the decline in U.S.-born workers paying into the system, Goss said.

Without immigrants, the Social Security Board of Trustees projects that the system will no longer be able to pay the full promised benefits by 2037.

Myth #3: They drain the system

Undocumented immigrants do not qualify for welfare, food stamps, Medicaid, and most other public benefits. Most of these programs require proof of legal immigration status and under the 1996 welfare law, even legal immigrants cannot receive these benefits until they have been in the United States for more than five years.

Related: Part-time jobs put millions in poverty or close to it.

Non-citizen immigrant adults and children are about 25% less likely to be signed up for Medicaid than their poor native-born equivalents and are also 37% less likely to receive food stamps, according to a 2013 study by the Cato Institute.

Citizen children of illegal immigrants -- often derogatorily referred to as "anchor babies" -- do qualify for social benefits. Also, undocumented immigrants are eligible for schooling and emergency medical care. Currently, the average unlawful immigrant household costs taxpayers $14,387 per household, according to a recent report by The Heritage Foundation. But in its 2013 "Immigration Myths and Facts" report, the U.S. Chamber of Commerce says most economists see providing these benefits as an investment for the future, when these children become workers and taxpayers.

A CBO report on the Comprehensive Immigration Reform Act of 2007 concluded that a path to legalization for immigrants would increase federal revenues by $48 billion. Such a plan would see $23 billion in increased costs from the use of public services, but ultimately, it would produce a surplus of $25 billion for government coffers, CBO said.

Myth # 4: They take American jobs

The American economy needs immigrant workers.

The belief that immigrants take jobs that can otherwise be filled by hard-working Americans has been disputed by an overwhelming number of economic research studies and data.

Related: Four immigration fixes that could turbo-charge tech.

Removing the approximately 8 million unauthorized workers in the United States would not automatically create 8 million job openings for unemployed Americans, said Daniel Griswold, director of the Cato Institute's Center for Trade Policy Studies, in his 2011 testimony before the House Judiciary Sub-committee on Immigration Policy and Enforcement.

The reason, according to the U.S. Chamber of Commerce, is two-fold. For one, removing millions of undocumented workers from the economy would also remove millions of entrepreneurs, consumers and taxpayers. The economy would actually lose jobs. Second, native-born workers and immigrant workers tend to possess different skills that often complement one another.

According to Griswold, immigrants, regardless of status, fill the growing gap between expanding low-skilled jobs and the shrinking pool of native-born Americans who are willing to take such jobs. By facilitating the growth of such sectors as retail, agriculture, landscaping, restaurants, and hotels, low-skilled immigrants have enabled those sectors to expand, attract investment, and create middle-class jobs in management, design and engineering, bookkeeping, marketing and other areas that employ U.S. citizens.

America's unions support the president's executive action. "For far too long, our broken immigration system has allowed employers to drive down wages and working conditions in our country," the AFL-CIO says on its website. "The brunt of the impact has been born by immigrant workers, who face the highest rates of wage theft, sexual harassment, and death and injury on the job."

Myth # 5: It's just a matter of following the law

Many Americans want immigrants to enter the country legally.

But under current immigration laws, there are very few options for legal immigration, the costs are increasingly prohibitive and the wait for any kind of status can be long and frustrating.

Related: I created 7 jobs and the US tried to deport me.

According to the State Department, that imaginary "immigration line" is already 4.4 million people long and depending on the type of visa sought and the country of origin, the wait can be years to decades long. In some countries, such as the Philippines and Mexico people have been waiting over 20 years for approval of a family-sponsored visa.

Immigrants can legally get to the U.S by being sponsored by an employer or a family member, they can enter the country as refugees, or they could receive one of the selectively distributed professional or diversity visas. The Diversity Visa Program makes 55,000 green cards available to persons from countries with low rates of immigration to the U.S.

According to the State Department, the fees to obtain permanent U.S. visas can range from $200 to over $700, excluding legal fees. Plus, there are visa quotas which limits immigration from any given country.

In many poor, violence-ridden countries, or in cases where parents are separated from their children, immigrants say the wait is unbearable, leaving many to resort to illegal border crossing.

That journey can be expensive and deadly.

Smugglers charge anywhere from $3000 to upwards of $70,000 depending on country of origin, mode of transport and distance travelled according to the Mexican Migration Project, a multidisciplinary research effort between investigators in Mexico and the U.S.

Many don't make it. According to federal records, more than 6,000 immigrants have died crossing the southern border since 1998