With less than a week to go before the Michigan primary, Rick Santorum is polling just ahead of Mitt Romney, but Romney is crushing him with people who've already voted absentee. A bird in the hand is worth two in the bush? Here's our guide to today's polls and why they matter.

Findings: In Michigan, Romney is easily beating Santorum among people who've already voted absentee, 49 percent to 26 percent. That's 16 percent of likely Republican voters. But among the majority of people who haven't voted yet, Santorum is ahead by a point, 37 percent to 36 percent.
Pollster: NBC News/ Marist
Methodology: Survey of 3,149 registered voters, 718 of them likely Republican primary voters, from February 19 to February 20.
Why it matters: One reason Romney had such a large victory in Florida was his campaign's push to get his supporters to vote early. "But while the Romney campaign’s early-voting organization is clearly helping him, a lack of support from conservatives is hurting him," NBC News' First Read writes. Santorum crushes him among Tea Partiers (48 percent to 29 percent) and very conservative voters (59 percent to 20 percent).
Caveat: Michigan has voted for a Democrat for president every year since 1992. The poll finds Obama ahead of Romney in the state 51 percent to 33 percent, and ahead of Santorum 55 percent to 29 percent. Republicans might be spending a lot of time there now, but they won't be in the fall.

Findings: Santorum beats Obama in Arizona 45 percent to 42 percent.
Pollster: NBC News/ Marist
Methodology: Survey of 2,487 registered voters, 767 of them likely Republican primary voters, on February 19 and February 20.
Why it matters: Santorum is still 16 percentage points behind Romney in Arizona, but he's beating Obama. Nationally, according to an Associated Pres poll, Obama is beating Santorum 52 percent to 43 percent. In December, Obama's reelection team presented reporters with five "paths" for the president to win 270 electoral votes. One of them involved winning Arizona. That still looks like a long shot.
Caveat: Obama's team thinks the immigration issue can rally more Latinos to polls.

Findings: Sen. Debbie Stabenow is beating Republican Rep. Pete Hoekstra in the Michigan Senate race by 21 points.
Pollster:  NBC News/ Marist
Methodology: Survey of 3,149 registered voters, 718 of them likely Republican primary voters, from February 19 to February 20.
Why it matters: In November, Hoekstra was within six points of Stabenow -- 42 percent to 48 percent, respectively. Ten days ago, Public Policy Polling found Stabenow with more than 50 percent of the vote, with Hoekstra falling to 37 percent. PPP's Tom Jensen declared that Hoekstra's racially-charged Super Bowl ad had "backfired." If that analysis is true, then the ad has hurt Hoekstra even more.
Caveat: PPP noted that Stabenow was still "under water with independents," with her favorable rating 40 percent and her unfavorable rating 47 percent.

Findings: 75 percent of Republican women have a favorable view of Santorum. Romney does not have an advantage with women over Santorum, as he did with his last challenger for the frontrunner spot, Newt Gingrich.
Pollster: Associated Press/ GfK
Methodology: Interviews with 1,000 adults from February 16 to February 20.
Why it matters: While the poll was being conducted, Santorum was in the news for his comments about birth control, as well as the remarks of his backer Foster Friess. They do not appear to have turned off Republican women.
Caveat: Sometimes it takes a while for a controversy to sink in -- Herman Cain peaked in polling after it was revealed he'd been accused of sexual harassment.