Flying in the face of findings by national pollsters, Guy Vander Jagt, chairman of the National Republican Congressional Committee, fore--casts that Republicans will make ''substantial and significant gains'' in House races this fall, Monitor correspondent Godfrey Sperling Jr. writes.
In fact, Representative Vander Jagt sees the possibility of the Republicans picking up enough seats to win control of the House.
Mr. Vander Jagt, talking to reporters over breakfast Wednesday, said there is an ''anti-incumbency'' feeling all around the United States these days and that this hurts the Democrats more than the GOP.
He sees an upturn in the economy helping Republicans in the fall elections. Another help will be the redistricting of congressional districts throughout the country, which Mr. Vander Jagt says will give the GOP about four new seats.
He said the Democrats in the House are receiving most of the blame from the public for the budget deadlock. He said they are being seen as causing chaos by refusing to go along with the Reagan budget and then not being able to come up with an alternative of their own.
Mr. Vander Jagt sees eventual passage of the Reagan-endorsed Michel-Latta budget resolution--with its authors adopting provisions that will bring more conservative Democrats behind the proposal. ''We will do this by moving just a little to the right,'' he said.