By Mark Willen, Senior Political Editor October 29, 2008 We've updated our electoral map to lean Nevada toward Barack Obama. Three polls of the state in the last 24 hours show him with an average lead of 9 percentage points, well beyond the margin of error. Nevada has a large Hispanic population that is strongly behind Obama. He's also benefiting from union support. We are also moving Maine and New Hampshire into solid Obama territory after multiple polls showing big and steady leads for the Democrat. In Pennsylvania, meanwhile, we see some signs of tightening, as John McCain pushes to turn this blue state red. Obama still has a comfortable lead there and we're not changing our forecast for the Keystone State, but we will be watching it closely in the final days of the campaign.Other late polling shows Obama holding leads in Ohio and Florida, but not by enough for us to move those states out of the toss-up category. Obama is also competitive in North Carolina, Missouri and Indiana, three states that are traditionally red and that McCain must win. Our overall count now has Obama leading in 24 states and the District of Columbia with 291 electoral votes, while McCain still leads in 21 states with 163 electoral votes. The remaining five states with 84 electoral votes could go either way. It takes 270 electoral votes to win the White House. Advertisement While all the polls show Obama leading nationally, his lead varies from 4 points to 15, depending on the poll. That's mostly because of the way different pollsters estimate who will actually show up on election day. The Washington Post has a good story explaining the discrepancies -- and why the McCain people still feel they have a chance to pull it out.