US Jews continue to back President Barack Obama over presumptive Republican nominee Mitt Romney, but support for the incumbent remains well below 2008 levels, according to a Gallup poll published Friday.Tracking from June 1 - June 26 found that Jewish registered voters favored Obama over his Republican challenger by 68 percent to 25%. This represents similar support levels as the last Gallup poll, taken in April-June 2012, which found that 64% of Jews supported Obama while 29% supported Romney. Romney was due to arrive in Israel Saturday for high-level meetings with Prime Minister Binyamin Netanyahu, President Shimon Peres, opposition leader Shaul Mofaz and Labor party head Shelly Yechimovich. A Republican group backed by casino magnate Sheldon Adelson has also unleashed a new campaign in battleground states to "convert" Jewish voters who have been life-long Democrats and who it is thought can be convinced to turn their backs on Obama.Gallup, however, predicted that US Jews, traditionally loyal Democrats, are "unlikely to become much more supportive of Romney," despite the intense Republican lobbying efforts.Polling both Jews and non-Jews on their opinions of Israeli leadership, Gallup found that Americans have a more positive than negative view of Prime Minister Netanyahu. However, the poll showed that for the first time more Democrats view Netanyahu unfavorably (31%) than favorably (25%.) This represents a change since 1999, during Netanyahu's last tenure as prime minister, when support was inverted (31% favorable to 25% unfavorable). Republicans, on the other hand, displayed growing support for the Israeli prime minister, with 50% viewing him favorably compared to 16% viewing him unfavorably. This compares well with 1999 levels, when 38% of Republicans viewed him favorably compared to 15% unfavorably.Though still overwhelmingly Democrat, US Jewish support for the the US president has dropped significantly since 2008 levels. The most recent Gallup poll shows a 12% decrease since since 2008 levels, when 74% of registers Jews supported Obama against then-Republican candidate John McCain.Republicans have mounted an intense campaign aimed at attracting Jewish voters to the their party.