By Susan Heavey and Rami Ayyub (Reuters) – Twitter’s new owner, Elon Musk, threw his weight behind Republicans ahead of Tuesday’s U.S. midterm elections, saying they could use control of Congress to act as a balance against President Joe Biden’s Democrats. The world’s richest person, Musk has faced criticism from some groups who believe his absolutist stance on free speech will increase misinformation on Twitter. Some advertisers have pulled spending from the platform, with Musk blaming critics concerned about content moderation. His tweet to more than 110 million followers on Monday represent…