Melania Trump's big night at the Republican National Convention failed to draw in bumper audiences to the major TV networks, according to early ratings data on Tuesday.

Preliminary data from ABC, NBC and CBS showed some 10 million Americans watched Monday evening's highlight, the 10 pm - 11 pm hour when the wife of Republican White House hopeful Donald Trump delivered her speech, later mired in accusations of plagiarism.

The early figures were down from the roughly 11 million people who watched the first night of the Republican national convention in 2012 on those networks. Updated figures, along with TV audiences from cable news channels and smaller networks, are expected later on Tuesday.

U.S. TV networks have boosted coverage of the Republican national convention this year after Trump drew huge audiences during the 2016 presidential debates.

Media analysts are predicting that viewership for Trump's acceptance speech this week for the Republican presidential nomination could surpass the record 38 million who watched Barack Obama address the Democratic convention in 2008.

In 2012, the Democratic convention generally drew more nightly TV viewers than the Republican gathering, when Mitt Romney was running for the White House.

On Monday, the most watched TV show of the night was reality show "The Bachelorette" which drew an audience of 6.6 million on ABC.

(Reporting by Jill Serjeant; Editing by David Gregorio)