How many congressmen in the us house of representatives does it take on any vote to have a majority?

There are currently a total of 435 possible members of the US House of Representatives who may vote on the House floor. If all Representatives are present and voting it would take 218 votes to have a majority. Often there are fewer present and voting so it is possible to have a majority with fewer than 218 votes. Also there is the possibility with a new Democrat Congress in 2009 that the District of Columbia might be given one or more vote(s) in Congress which could change the answer above. Whether DC gets a vote without any other adjustment to the membership numbers (subtracting one or more from other states), DC gets a vote by adding more representatives to the 435 total, or DC gets a vote along with additional representatives allotted to another state (for example, Utah, as proposed in the last few years), is not yet determined.