Latvian President Raimonds Vejonis, right, looks at US Sen. John McCain centre left, during a press conference, Wednesday in Riga, Latvia, while Lindsey Graham, R-SC., and Amy Klobuchar, D-Minn., stand in the background. Russia can expect hard-hitting sanctions from United States lawmakers if an investigation proves that Moscow interfered in the presidential election, a U.S. senator said Wednesday during a visit to Latvia.