NEW YORK (CNN/Money) - Stocks posted big gains Tuesday as investors scooped up beaten-down insurance stocks in a rally that spread to the broader market.

The Dow Jones industrial average (up 138.49 to 9,888.48, Charts) jumped 1.4 percent and the broader Standard & Poor's 500 (up 138.49 to 9,888.48, Charts) index added around 1.5 percent.

The Nasdaq composite (up 14.75 to 1,928.79, Charts) rose nearly 0.8 percent.

Gains were broad-based, with 27 out of 30 Dow issues gaining. Insurer AIG was the Dow's biggest advancer, gaining about 7.5 percent.

The insurance sector snapped back Tuesday, after having been hammered recently amid allegations of cheating customers through bid-rigging. Investors also took comfort in news that no criminal charges would be filed against Marsh & McLennan, after its CEO, Jeff Greenberg, stepped down Monday.

The rally in insurance gave the rest of the market a leg up, though analysts cautioned that the move was mostly technical.

"It's an oversold bounce," said Art Hogan, chief market analyst at Jefferies & Co. "After you get oversold, you have a reflex rally, and that's what we're seeing now."

Nonetheless, the rally helped investors shrug off the latest rise in oil prices and the morning's weak consumer confidence report. It also eased jitters about next week's presidential election.

Wednesday brings earnings from Dow components Boeing (Research) and Procter & Gamble (Research), as well as Comcast (Research).

(For a preview of the key earnings due in the week ahead, click here.)

Wednesday also brings reports on durable goods orders, new home sales and oil and gas crude supplies.

New home sales, due Wednesday, are expected to have fallen to a 1.150 million unit annual rate from a rate of 1.184 million units in August.

Wednesday morning also brings the report on durable goods orders. Orders probably rose 0.5 percent in September, according to estimates, after falling 0.3 percent in August.

Shares of Marsh & McLennan (up $2.45 to $28.87, Research) jumped 9.3 percent after the company said after Monday's close that its embattled CEO resigned, leading New York Attorney General Eliot Spitzer to say his office won't pursue criminal charges against the company.

But the stock has still fallen sharply since the Spitzer news first broke, Hogan said, so a small bounce was not particularly significant.

A variety of healthcare insurers gained on the news, too.

Homebuilders gained after Pulte Homes (up $3.02 to $54.52, Research) gave an improved outlook. The company said late Monday that it expects fourth quarter and fiscal 2005 earnings to top estimates. The company also reported third-quarter results that rose from a year ago and met expectations.

The Dow Jones home construction (Charts) index added 3.5 percent.

Delta Air Lines (up $0.85 to $4.63, Research) rallied 22.2 percent in active New York Stock Exchange trade. The stock gained on increasing analyst speculation that the carrier may not need to file for Chapter 11 bankruptcy in the near term, due to new financing and talks with its pilots. JP Morgan upgraded it to "neutral" from "underweight."

General Electric (up $0.73 to $33.63, Research) rose two percent after saying it is on track to meet its 2004 earnings forecast and to hit double-digit gains in earnings per share in 2005.

nVidia (up $1.15 to $14.49, Research) shares gained 8.6 percent after the graphics chipmaker said third-quarter results will top estimates due to improved market share.

On the downside, Flextronics (down $0.87 to $11.67, Research) fell around 7 after issuing a fiscal third-quarter forecast late Monday that was short of expectations. The forecast overshadowed the contract manufacturer's in-line fiscal second-quarter results.

Qualcomm (down $1.64 to $39.50, Research) lost four percent after Morgan Stanley downgraded it to "underweight" from "equal weight," saying that the stock has gotten expensive relative to the sector and 2005 will likely be a transition year for the company.

Chipmaker Silicon Laboratories (down $6.56 to $27.88, Research) plunged 19 percent after saying that fourth-quarter results will miss estimates due to excess inventories and a global economic slowdown. The warning overshadowed the company's improved third-quarter earnings, sending shares lower.

Market breadth was positive. On the New York Stock Exchange, advancers topped decliners by more than eleven to five on volume of 1.68 billion shares. On the Nasdaq, winners topped losers three to two as 1.80 billion shares traded.

Investors seemed to take in stride a weaker-than-expected consumer confidence report, released around 30 minutes after the start of trading.

The Conference Board's consumer confidence index fell to 92.8 in October from a revised 96.7 in September. Economists surveyed by Briefing.com thought confidence would fall to 94.

Treasury prices fell, pushing the 10-year note yield up to 4 percent from 3.97 percent late Monday. Treasury prices and yields move in opposite directions.

The dollar inched higher versus the yen and euro.

COMEX gold fell $2.20 to settle at $427.60 an ounce.

Crude oil initially fell after Norway ordered workers to end a strike that could have threatened exports from the country. However, prices turned around by late morning. U.S. light crude for December delivery rose 63 cents to $55.17 a barrel on the New York Mercantile Exchange.

Polls show President Bush and Sen. John Kerry remain in essentially a dead heat, creating nervousness for a market that likes certainty.

Whether the market would prefer Bush's reelection or a Kerry victory is less clear cut lately.

Traditionally, Wall Street is said to prefer the Republican Party, in that it is more "big business friendly." Investors are also said to like the comfort of an incumbent serving a second term, which would suggest that Wall Street would like to see Bush win. Additionally, the Democratic challenger, John Kerry, has vowed to roll back some of the Bush tax cuts if elected.

However, statistics show that stock markets tend to perform better and to be less volatile under Democratic administrations.

Additionally, recent reactions suggest that Wall Street has gotten more comfortable with the possibility of a Kerry victory. This speaks to the fact that regardless of who wins the election, Congress is likely to remain Republican, which would temper any big changes a President Kerry might try to enact.

The weakness in the stock market during October and in 2004 may imply that Kerry could win, according to historic data compiled by the Stock Trader's Almanac.

Generally, in an election year, a Dow gain in October is good news for the incumbent and a Dow decline in October is good news for the challenger. The Dow is down nearly 2 percent for the month, as of Tuesday's close.

Additionally, the Almanac looked at the 26 elections since 1900.

The 16 times in which a party retained the White House, the Dow on average gained 15.8 percent during the election year. The 10 times an "in" party was ousted, the Dow on average lost 1.4 percent during the election year. The Dow is currently down around 5.5 percent year to date, as of Tuesday's close.

For some investors, a bigger worry is not which party will win, but whether any party wins on Nov. 2, with many fearing a repeat of what happened in 2000, when an undecided election left the country on edge for more than a month until the Supreme Court intervened.

"I think people are very worried that this is going to stretch out, particularly if it's close," said Tom Schrader, managing director of listed trading at Legg Mason. "No one knows who is going to win, or when they will win, and there's still talk of terror activity around the election."