DES MOINES – In his years-long bid for the White House, there has been perhaps no more elusive prize for Mitt Romney than Iowa.

It was the state that propelled the former Massachusetts governor into national contention, handing him a decisive win in the 2007 Ames straw poll. But it has remained just out of his reach ever since, voting for dark horse former Arkansas governor Mike Huckabee in the 2008 GOP caucuses and giving former Pennsylvania senator Rick Santorum a razor-thin victory over Romney four years later, in a race that was so tight that it went to a recount. Both candidates’ victories were fueled by the state’s evangelical population, a critical voting bloc in the first-in-the-nation caucuses.

On Sunday morning, the Republican presidential nominee returned to Des Moines in one last bid to capture the state and, if things go his way Tuesday night, the White House.

“Talk is cheap, but a record is real and it’s earned with real effort,” Romney told a boisterous crowd of 4,000 supporters at the Hy-Vee Hall downtown, reprising his stump-speech appeal for them to reach out to friends and neighbors who may still be undecided. “You can’t measure change in speeches. You measure change in achievements.”

There were encouraging signs for Romney ahead of his arrival in the state. Last week, the Des Moines Register, which backed then-Sen. Obama in 2008, endorsed Romney, arguing that voters should give him “a chance to correct the nation’s fiscal course and to implode the partisan gridlock that has shackled Washington and the rest of America — with the understanding that he would face the same assessment in four years if he does not succeed.”

The Romney campaign touted the endorsement on a large TV screen at Sunday morning’s event, and as he took the stage, the candidate told the crowd that he wanted to give “a special shout-out to the Des Moines Register -- thanks for your endorsement.”

But there were other signs that the battle for the Hawkeye State’s six Electoral College votes remains an uphill one for Romney. The Des Moines Register’s latest Iowa Poll, released Saturday night, showed Obama taking 47 percent to Romney’s 42 percent. The survey had a 3.5 percentage point margin of error.

The newspaper on Sunday morning ran dueling op-eds from both campaigns – one by GOP vice presidential nominee Paul Ryan on behalf of the Republican ticket, and another by former president Bill Clinton on behalf of the Obama campaign.

At Sunday’s event, Romney was introduced by a number of speakers including Rep. Tom Latham (R-Iowa ), Republican congressional candidate John Archer (Iowa), Sen. Chuck Grassley (R-Iowa) and Iowa Gov. Terry Branstad (R), who told the crowd that while “four years ago many Iowans took pride” in watching Obama’s rise, the president has failed to live up to his promises.

Branstad told the audience to cheers that “if Obama wants to take credit for the economy, let him take credit for it in Illinois” and other blue states rather than states led by Republican governors such as himself.

“It’s time for you to go back to Chicago!” he said of Obama.

Romney also was preceded at the event by the Oak Ridge Boys, who recently warmed up the crowd at a Romney-Ryan rally in the battleground of Ohio. As at that event, one of the members of the group took a shot at Obama by telling the crowd of how the group had been invited by Romney to sing “Amazing Grace” at the GOP convention, and “how cool it was to have a future president want to hear Amazing Grace.”

Romney took the stage to big cheers and delivered nearly the same closing argument as he has on the road in recent days, reading from teleprompters.

“Two more days and we can get to work rebuilding our country, restoring our confidence and renewing our conviction. ... On Nov. 7, we’ll get to work. We’ll reach across the street to that neighbor with that other yard sign, and I’ll reach across the aisle to people in the other party,” Romney said to cheers.

Staff writer Philip Rucker contributed to this report.