His eyes turned more than ever toward John McCain and the national election contest, Barack Obama will make a symbolic return trip to Iowa tonight even as results from the primary votes in Kentucky and Oregon begin to flow in.
Despite the fact that today's results are likely for the first time to give Mr Obama a simple majority of so-called pledged delegates – those apportioned according to the state-by-state primary and caucus votes – he is expected to hold back from declaring himself winner of the nomination race. He is anxious not to alienate supporters of Hillary Clinton, whose help he will need to defeat John McCain in November.
Mrs Clinton should handily win in Kentucky but lose in Oregon, where on Sunday Mr Obama addressed his largest rally yet, with an estimated 75,000 voters turning out. "Wow, wow, wow!", were his first words on taking the podium.
The mere fact of appearing in Iowa will be a signal of his confidence of prevailing over Mrs Clinton. Iowa not only kicked off the nomination process on 3 January, but supercharged the Obama quest by handing him a surprise victory. It was a shock from which the Clinton camp has never properly recovered.
He acknowledged over the weekend that holding a rally in Des Moines, Iowa, was a "terrific way to kind of bring things full circle". Tomorrow, Mr Obama, who last night won the symbolic endorsement of Robert Byrd, the oldest member of the Senate, will campaign in Tampa, Florida – one of two states, along with Michigan, disqualified from the nomination process for voting early.
Mrs Clinton is holding out hope of persuading a meeting of the party's rules committee next week to reconsider their punishing of Florida and Michigan and reinstate delegates from both states, a move that could help close the gap with Mr Obama – though by no means erase it. She is unlikely to win the argument outright, though there may be a compromise.
Increasingly, however, Mrs Clinton is looking like an irrelevant force. Instead, the noise of battle is coming from clashes between Mr Obama and Mr McCain. Yesterday, the Republican nominee chose a speech before the National Restaurant Association in Chicago to slice into both Democrats on economic issues.
The attacks come at a time of barely disguised panic in his party in the wake of losing a supposedly safe congressional seat in northern Mississippi to the Democrats last week. It was the third such seat snatched away in recent months, raising fears that Republican representation on Capitol Hill may be eviscerated in November, when Americans will also be choosing their Congress.
It has escaped no one's notice that attempts by the losing Republican candidates to tarnish their Democrat opponents by associating them with the supposedly "hyper-liberal" Mr Obama flopped with the voters. Reluctantly, party strategists are acknowledging that the only hope for them this year – Mr McCain included – will be to put as much distance as possible between themselves and President George Bush.
How far Mr McCain can take that path remains to be seen, as he wavers between wooing sceptical conservatives, who remain loyal to Mr Bush, and his party's more moderate centre. His other problems include finding ways to boost his fund-raising record, which looks increasingly flimsy beside Mr Obama's. Mr Bush may still be critical to that effort.
"We are not running against the President; we're running against one of these Democrats," one McCain adviser, Charlie Black, insisted. That certainly appeared the focus of Mr McCain yesterday. "Under the various tax plans of both Democratic candidates, parents, seniors, small business owners, and Americans of every background would pay thousands of dollars in new taxes," he said.Reuse content