Democratic front-runner John Kerry notched easy wins in Nevada and the District of Columbian last night to expand his lead in the party's presidential race, while rivals Mr Howard Dean and Mr John Edwards focused on stopping his winning streak in Wisconsin on Tuesday.
With the nomination almost in his grasp, Mr Kerry kept his sights trained on a November matchup with President George W. Bush and accused him of "attack politics" designed to hide his poor record in the White House.
"Given the record of this administration and their stunning lack of vision, the Republican attack machine may well have no choice but to resort to smear and to fear," Mr Kerry said at a party dinner in Milwaukee.
"They can gear up their attack machine, but I'll tell you what: They can't escape the truth. November is coming, George W. Bush is going," he said.
Mr Kerry easily beat second-place finisher Mr Dean in Nevada, 63 per cent to 17 per cent. In Washington, D.C., Mr Kerry beat civil rights activist Mr Al Sharpton, who finished second, 47 per cent to 20 per cent.
The two wins give Kerry victories in 14 of the first 16 contests in the race to find a Democratic challenger to Bush.
They also set up a crucial showdown in Wisconsin on Tuesday with Mr Dean, the fallen front-runner, and Mr Edwards, the senator from North Carolina.
The Wisconsin primary could be the last chance for either of the Massachusetts senator's rivals to halt his momentum before a March 2nd round of 10 contests in states like New York and California that could virtually clinch the nomination.