US Republican Senator Jerry Moran (2nd, R), chairman of the National Republican Senatorial Committee (NRSC), speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

Reince Priebus (2nd, R), chairman of the Republican National Committee, speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

Reince Priebus (2nd, R), chairman of the Republican National Committee, speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

Luis Fortuno (2nd, L), former governor of Puerto Rico, speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

Reince Priebus (C), chairman of the Republican National Committee, speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

US Republican Senator Jerry Moran (2nd, R), chairman of the National Republican Senatorial Committee (NRSC), speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)

Greg Walden (2nd, L), chairman of the National Republican Congressional Committee (NRCC), speaks during a press conference at the Republican National Committee's headquarters in Washington D.C., capital of the United States, Nov. 5, 2014. Republicans gained majority in the US Senate and widened control of the House of Representatives in midterm elections on Tuesday. (Xinhua/Bao Dandan)