DES MOINES, Iowa -- Returning for the final time to the state that launched the 2012 campaign so many months ago, Mitt Romney asked Iowans on Sunday morning to support him one last time, by casting their ballots for the "change" candidate on Tuesday.

"I need your vote, I need your work, I need your help. Walk with me. We’ll walk together. Let’s begin anew," Romney said in closing here, his voice showing strains from days of frenetic campaigning. "I need Iowa – I need Iowa so we can win the White House and take back America, keep it strong, make sure we always remain the hope of the earth. I’m counting on you!"

A crowd of more than 4,000 supporters turned out for Romney's Sunday morning Iowa finale, in which the GOP nominee delivered his now-familiar closing argument stump speech calling on undecided voters to "look beyond the speeches and the attacks and all the ads," and make their final choice based on records, and who they believed stood the best chance to enact "real change" in the next four years.

"Talk is cheap.  But a record is real and it’s earned with real effort," Romney said. "Change – you can’t measure change in speeches.  You measure change in achievements.”

Romney has looked to strike a hopeful, optimistic tone in the final days of a campaign, which Sunday's newest NBC News/Wall Street Journal poll shows remains deadlocked nationally, with Obama claiming 48 percent of the vote to Romney's 47 percent. Romney advisers concede they're likely narrowly behind in Iowa based on early voting totals and internal polling, but remain confident Romney can win the state with a strong showing from Republican voters and independents on Election Day.

Attacks against the president, calibrated to appeal to those independent voters, remained in this final appearance. Romney criticized the president for asking supporters to vote based on revenge for the sixth-straight rally ("Voting is the best revenge," Obama said in Ohio on Friday; an off-the-cuff remark quickly grafted into Romney's stump speech), and during his introduction of Romney, Iowa's Republican Gov. Terry Branstad accused the president of betraying Iowans natural fiscal restraint.

"Iowans feel betrayed. Almost a sense of -- not only disappointed, but almost a sense of betrayal that our principles of sound budgeting and responsible government have been ignored by this administration for four straight years," Branstad said. "Iowa's message for Obama is: It's time for a change. It's time for you to go back to Chicago."